Set mark eliminator



March 10, 1953 c. R. BEALL 2,630,838

SET MARK ELIMINATOR Filed March 4, 1949. 2. SHEEfiv-SHEET l ci iaw 2 35 3.9 4

1e 23 ChwrlesIl-Beall A TTOR N EYJ C. R. BEALL SET MARK ELIMINATOR Filed Max-ch 1949 l 'Bea/M ATTORNEYS Patented Mar. 10, 1953 UNITED STATES PAT QFFI CE SET. MARK ELIIVHNATOR Charles R. Beall, La Grange, Ga., assignor to West Point Manufacturing Company, West Point, Gran,v a. corporation of- Alabama ApplicationsMarch i, 1949, Serial-N0. 79,643

9 Claims. 11

This inventionirelates to-looms, and more particularly to warp beam driving mechanism for looms.

During the weaving of textiles, the. warpis commonly subjected to tension between the warp beam and the-c1oth take up roller. In the case of many yarns, such asthose spun of short fibers of wool or cotton, and.- extruded; filaments, such as. those of cellulose acetate, the warp tension causes thewarp to-setor stretch during overnightfand other periods of shut-down.

When a loom is-started after a period of shutdown, the: first. several filling. threads, due to the set of the warpand-theresulting slackening of tension, are not spaced similarly to. the last fillingthreads insertedv preceding shut-down. The resulting unevenness in filling thread spacing is known as a setmark, andis the cause of rejection of considerable quantitiesof cloth.

It is an object of the present invention to provide means, readily incorporated into conventional looms, adapted to eliminate the. formation of set-marks by restoring the desired warp tension when a. loom is started. after a period of vision of means for deactivating the. let-off mechanism of a loom whenthe loom is. started, and=sin'lultaneeus1yv turning back the warp beam of. the loom to increase the tension of the warp.

A still further object is-the provision. of means for automatically-turnmg-back the warp beam of a loom when the loom isstarted, and thefurther provision of means controllable-tovary the extent of such turn-back.

Other objects of the inventionwill be in part obvious and in part; pointed: out hereinafter.

The invention and. the novel featuresthereof may best be made: clear from the following. description: and the accompanying drawings, in which:

Figure 1. is-a, side View of a conventionalloom, provided. with, apreferred embodiment of i the present invention;

Figure. 2 is an enlarged, detailed view correspending, to Figurel, showing with greater particularity the means for turning back the warp beam;

Figure. 3-is a. partial section taken on the line 3r-3' of-Figure 1;.

Figure: eisaperspective viewof the warplet- 21' off mechanism drive and the, associated warpturn-back mechanism, and.

Figure 5 is a diagram ofthe turn-back mechanism control circuit.

Referring .to the drawings, Figure I shows a preferred. embodiment. of i the present. invention; incorporated into a, conventionalloom,.such asja; DraperX Model 1oom,.comprising the usual frame it the warp beam II, and the shipper lever l2;

by displacement of'whichthe'loom' is started and stopped. The warp beam II is'positivel'y' driven to let ofi the warp in step-by-stepfashion through the beam gear I3 by the pinion i4; actuated-by the reciprocating motion ofthe rockerv arm l-5 extending, from the lay'rock shaft H3: The recip--- rocating motion of rocker'arm l5 is-transmitt'ed to pinion M by the link IT'andthe crank -l8-;op"-- erative, to reciprocate the pawl'carrier l9 andthe pawl 29. associated therewith, and thereby dis-- place the ratchet wheel 21"instepby-stepfash' ion.. The ratchet wheel'2i incommon with pinion I4, is mounted on the-shaft 22: The above described let-off mechanism is well known, and does not constitute a part of the'present invention.

On an extension of shaft 2 2 isaffixed the-turn back ratchet wheel 23; with" teeth arranged re versely to those of ratchet wheel 2!: The pushpull rod 24 is slidably'supported above turn-back ratchet wheel 23 by the guide- 251 extending-from frame l0. Shipper lever l2- is-operati vely'connected'to .push-pulrrod zrmdriving relationship by the rod: Zt-and'thelink- 21; pivotally securedito opposed" ends of the bellcrank 2 B-mounted on frame Ii}by-means-ofthepivot29a- As best seen in Figure 2; the sleeve 30 is secured to push-pull rod 24' by the set screw 31, and the turn-back pawl 32' is pivotally supported above turn-back ratchet wheel 23" by the-pin 335 retained-between the flanges 3'4 extending downwardly from-sleeve 3th The spring .35" is stretched between sleeve 30 andthetail sfifoftum back pawl 32'; and urges the turn-back pawl toward-j turn-back ratchet wheel 23; The stop, 3lisqprovided'ontail 3ii'to suitably limit the movement thereof;

The. solenoidsa is suitably'm'ounted on' the side of sleeve 30 andpartially'enclosesr-the'plunger 38,. which is pivotally secured to th'e'jlug 40 ex tending from turn-backpawl 32, 'as'bythe' pin H The fiexibl'e'conduit 42 conductsithe wires 43143 from solenoid 3I8j'to the junction" box 44'; wherein solenoid'38is connected'ito a source of'power and through the flexible conduit 45 to the button switch 46,.mounted', for the sake" of" convenience, onrthe handleof shipper lever12i- Also suitably secured to push-pull rod 24 and spaced therealong from sleeve 30 is the cam sleeve 41, from which depends the oiiset cam 48, positioned and adapted to engage and depress the cam following tail 49 of pawl 28 in passing thereover.

During the periods of shut-down, shipper lever I 2 and the associated mechanism of this invention is in the position best shown in Figure 1, and in solid lines in Figure 2. The loom is started by moving the shipper lever 12 forward to the position shown in dotted lines in Figure 2. Movement of the shipper lever [2, it will be readily seen, causes corresponding movement of the rod 26, which movement is reversed in direction by bell crank 28 and transmitted through link 21 to the push-pull rod 24, causing the pushpull rod and the associated turn-back pawl 32 to traverse across the turn-back ratchet wheel 23, to the position shown in dotted lines in Fig ure 2. At the same time, the cam 48 is caused to traverse across the tail 49 of driving pawl 20.

When the loom is not operating, turn-back pawl 32 and cam 48 occupy the positions best shown in Figure 1, out of engagement, respectively, with turn-back ratchet wheel 23 and tail 49. In the course of the traverse of push-pull rod 24, occasioned by movement of shipper lever l2 to start the loom, turn-back pawl 32 successively engages turn-back ratchet wheel 23, displaces the turn-back ratchet wheel in the direction of the arrow 50, and moves out of engagement with said ratchet wheel to assume the position shown in dotted lines in Figure 2, where it remains while the loom is operating. Simultaneously, the cam 48 engages and depresses the tail 49 of pawl 20, thereby maintaining pawl 20 out of engagement with ratchet wheel 2| until the cam passes beyond the tail and assumes the final position shown in dotted lines in Figure 2, where it remains during the operation of the loom. When the loom is stopped by returning shipper lever l2 to the off position, the push-pull rod traverses to the left as shown, turn-back pawl 32 clicks over turn-back ratchet wheel 23 to resume its former position, and cam 48 passes over the pawl 20 to resume its former position.

It has been found that by restoring the warp tension prevailing before shut-down, upon starting the loom, the spacing of the first few filling threads inserted on starting up is substantially identical with that of the last few filling threads inserted before shut-down, and the formation of a set mark is obviated. The amount of turnback necessary to return the warp to the tension prevailing before shut-down will, of course, vary with the type of yarn being woven, the duration of the shut-down, and other variables. It has been found that a moderately experienced operator can readily gauge the amount of turnback necessary to accurately adjust the warp tension and prevent formation of set marks.

I The throw of push-pull rod 24 and the vertical spacing of turn-back pawl 32 relative to the turn-back ratchet wheel 23 are desirably adjusted to effect an operative throw of the turnback pawl corresponding to the maximum displacement of the warp turn-back mechanism likely to be needed under normal conditions expected to be encountered. Similarly, the operative length of the cam 48 is suitably adjusted to deactivate the pawl 20 during the engagement of the turn-back ratchet wheel by the turn-back pawl. The operative throw of turn-back pawl 32 is conveniently varied downwardly from its maximum by means of solenoid 38. To effect this adjustment, the operator may, in starting the loom by means of shipper lever 12, depress button switch 46 during a portion of the travel of the shipper lever, thereby energizing solenoid 38 and causing the turn-back pawl to be held out of engagement with the turn-back ratchet wheel during the corresponding portion of the traverse of the turn-back pawl. Release of the button switch 46 during the remainder of the movement of the shipper lever allows the turnback pawl to fall back and engage the turnback ratchet wheel during the remaining portion of its traverse. In this manner, the operator may vary the amount of turn-back effectuated by movement of'shipper lever [2, as may in his judgment be necessary. It will be apparent that the operative throw of the turnback pawl may be made adjustable in other ways, mechanically or otherwise. Similarly, it will be apparent that other suitable means may be provided for deactivation of the let-01f mechanism drive.

In the event of a shut-down of such short duration as not to cause any set of the warp, it will be evident that the button switch 46 may be depressed during the entire throw of shipper lever I2, in this manner starting the loom without any turn-back of the warp beam. In the circumstance that more turn-back is needed than is provided by the maximum operative throw of the turn-back pawl 32, the necessary amount of turn-back may be secured by repeated manipulation of the shipper lever back and forth, and the corresponding repeated operation of the associated mechanism of this invention.

While the warp beam turn-back mechanism of this invention has been shown, in the specific embodiment illustrated, as associated with a specific type of let-ofi mechanism, it will be apparent to those skilled in the art that the turn-back mechanism may drive the warp beam independently, or in association with other letoif mechanisms.

It will thus be seen, that there has been provided by this invention an apparatus in which the various objects hereinbefore set forth, together with many practical advantages, are successfully achieved.

As various possible embodiments may be made of the mechanical features of the above invention, all without departing from the scope there- -of, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In combination with a loom, a shipper lever whereby said loom is started and stopped, a warp beam, let-off mechanism whereby said warp beam is actuated to let off the warp, and means operable by said shipper lever to temporarily deactivate said let-off mechanism and simultaneously turn back said warp beam a predetermined distance when said shipper lever is displaced to start the loom.

2. The invention as defined in claim 1, including means for varying the extent of operation of said turn-back means.

3. In combination with a loom, a shipper lever whereby said loom is started and stopped, a warp beam, let-on" mechanism whereby said warp beam is actuated to let off the warp, a ratchet in oner ative relationship with said warp beam, a pawl adapted to engage and displace said ratchet to turn back said warp beam, and means operable by said shipper lever to temporarily deactivate said let-off mechanism and simultaneously actuate said pawl when said shipper lever is displaced to start the loom.

4. The invention as defined in claim 3, including means for varying the operative throw of said pawl.

5. In combination with a loom, a shipper lever whereby said loom is started and stopped, a warp beam, let-oil mechanism whereby said warp beam is actuated to let off the warp, a ratchet in operative relationship with said warp beam, a pawl adapted to engage and displace said ratchet to turn back said warp beam, a mechanical linkage between said shipper lever and said pawl operable to actuate said pawl when said shipper lever is displaced to start the loom, and means associated with said mechanical linkage for deactivating said let-ofi mechanism during the operation of said pawl.

6. The invention as defined in claim 5, including a solenoid in association with said pawl operable to withhold said pawl from engagement with said ratchet during energization of said solenoid.

7. In combination with a loom, a shipper lever whereby said loom is started and stopped, a warp beam, let-ofi mechanism including a driving ratchet and driving pawl whereby said warp beam is actuated to let oil the warp, a turnback ratchet in association with said driving ratchet and oppositely disposed relative thereto, a turn-back pawl positioned and adapted to engage and displace said turn-back ratchet to turn back said warp beam, a mechanical linkage between said shipper lever and said turnback pawl operable to actuate said turn-back pawl when said shipper lever is displaced to start the loom, and means associated with said mechanical linkage for deactivating said driving pawl during the operative throw of said turnback pawl.

8. The invention as defined in claim '7, including a solenoid in association with said turnback pawl operable to withhold said turn-back pawl from engagement with said turn-back ratchet during energization of said solenoid.

9. In combination with a loom, a shipper lever whereby said loom is started and stopped, a warp beam, a driving ratchet and driving pawl associated with said warp beam in driving relationship and adapted to rotate said warp beam to let ofif the warp, a turn-back ratchet in association with said driving ratchet and oppositely disposed relative thereto, a turn-back pawl positioned and adapted to engage and displace said turn-back ratchet to turn back said warp beam, a mechanical linkage between said shipper lever and said turn-back pawl operable to actuate said turn-back pawl when said shipper lever is displaced to start the loom, a cam associated with said mechanical linkage adapted to engage and inactivate said driving pawl in the course of displacement of said shipper lever, and a solenoid in association with said turn-back pawl operable to withhold said turn-back pawl from engagement with said turn-back ratchet during energization of said solenoid.

CHARLES R. BEALL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 829,689 Benson Aug. 28, 1906 2,421,539 Clarke June 3, 1947 2,430,639 Jacques Nov. 11, 1947 

